The isolated perfused rabbit liver was used to compare the acute effects of alcohol and amino acids on albumin synthesis, polysomal aggregation, and RNA turnover. The perfusion solutions were modified to contain test amino acids in a final concentration of 10 micromolar and/or alcohol was added and maintained at 220 miligrams per 100 ml. Albumin synthesis was determined isotopically and immunologically and the methods agreed well. H3 uridine was added to the perfusion solution to label newly synthesized RNA. Fasting reduced albumin synthesis 50%, and the endoplasmic reticulum-bound polysome was disaggregated. The amino acids, tryptophan, arginine, ornithine, lysine, phenylalanine, glutamine, alanine, threonine, and proline increased albumin synthesis toward or exceeding the value found in the fed control, and the endoplasmic membrane-bound polysome was reaggregated. Leucine, valine, methionine, and histidine failed to stimulate albumin synthesis or cause reaggregation. The RNA of the bound polysome achieved 60% of the specific activity of that in the free polysome in the fed control preparation, and no change occurred with fasting or after the stimulating amino acids. Total RNA was decreased in fasting and rose after perfusion with the stimulating amino acids. Alcohol likewise reduced albumin synthesis by 67% and caused marked disaggregation of the endoplasmic membrane-bound polysome. Arginine, tryptophan, ornithine, and lysine reversed this depression, and reaggregation with the endoplasmic membrane-bound polysome occurred. Alcohol however, reduced the bound to free relative specific activity ratio, and the addition of stimulating amino acids returned this ratio toward normal. No loss in RNA was noted.